This application relates to a method for evaluating a tissue of biopsy sample to determine if the sample is early stage melanoma. The method relies on the observation that Id1 protein, one of a class of Id proteins which inhibit DNA binding by transcriptional regulatory proteins, is expressed in early stage melanomas, but not in benign specimens nor in invasive or metastatic melanomas. In tumors with in situ and invasive portions, only the in situ part of the tumor expresses Id1.
It has previously been shown in Published PCT Application W097/05283, which is incorporated herein by reference, that Id proteins, or the nucleic acids encoding such proteins, can serve as diagnostic markers for identifying tumors which may be susceptible to treatment by chemotherapy and radiation. This patent shows data suggesting the ability to use Id1 to distinguish between rhabdomyosarcoma (RMS) and normal muscle cells, but offers no insight concerning melanoma.